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Comment by evunveot | Hacker News Reader

From what I've read, we've already identified the specific bacteria responsible for tooth decay [1], but there seems to have no interest in developing treatments based on that insight. Instead we're supposed to essentially sterilize our mouths and remineralize our teeth (which is something saliva does naturally) with topical fluoride twice a day.

My cat has never brushed her teeth, and they're fine, presumably because the microbiome in her mouth is in a state where bacteria that secrete lactic acid are crowded out by benign species. Granted, she doesn't eat many simple sugars, but I have had a vet recommend brushing her teeth twice a day as a preventative measure, which blew my mind.

I hope I live to see the day when the extent of oral hygiene maintenance and bad breath prevention is a toothpick and an occasional probiotic mouthwash or something.

[1] https://en.wikipedia.org/wiki/Dental_caries#Bacteria

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Have you seen a 50 year old cat? I bet their teeth would be completely rotten.

Okay so house cats don't live that long.. but look at longer living mammals like horses. Their teeth are terrible at 20 years old.

I think the human teeth will do fine without brushing for 20-30 years, enough to make babies. They aren't really designed for the 75 year life plan..

I could be totally incorrect about this theory, but I thought that's why we get wisdom teeth around that mark, since we would be essentially without teeth at that point in our life if we had went a lifetime without brushing.

Surprisingly, the longest-lived housecat on record lived 38 years [1]. Much longer than you'd expect given that an average lifespan is just 12-15 years.

[1] https://en.wikipedia.org/wiki/Creme_Puff_%28cat%29

I know tons of people under 30 who have a lot of cavities.

Sure but the can smash up food well enough to live.

Have you not owned a lot of cats? Tooth decay in cats is a really common problem. Both our cats have needed teeth pulled.

Fair enough. My cat is only four years old. But my point is that we treat tooth decay like an inevitable consequence of failing to brush and floss when we actually know it's caused by the blooming of certain specific bacteria. Brushing with fluoride helps enamel resist the decay, but it does nothing to prevent the bad bacteria from blooming again in 12 hours.

Admittedly, I hate taking care of my teeth and thinking about things this way comforts me when I fail to do so.

Tooth decay has plagued humanity since before recorded history. Before dentistry, it used to kill people. It routinely kills animals in zoos. Presumably it kills them in the wild, too --- just, more slowly and painfully.

Which is not to moralize about your own dental hygiene. Dealing with the consequences of poor dental hygiene is what dentists are for. :)

Certainly wasn't my intention to engage in paleophilia (which unfortunately means sexual attraction to dinosaurs according to Urban Dictionary; I'm talking about the unreasoned assumption that anything humans experienced pre-civilization must be more "natural" and thus beneficial). I acknowledge that in the absence of a consistent oral hygiene regimen the health of my and my cat's teeth is at risk. I also hope that science will some day save both of us from some or all of the tedium and expense.

Tooth decay in England only became a major issue from the Tudor period onwards when readily available sugar was introduced the food supply

I don't know what "major issue" is, but there is evidence of paleolithic dentistry, long before there were sugar crops.

This made the news awhile ago, it's called STAMP (specifically targeted antimicrobial peptides). Here's a 2011 article that seems to show some progress.

http://www.ncbi.nlm.nih.gov/pubmed/21860239

Wow, sounds promising. Is that something you can buy?

Evora will be glad to sell you probiotic lozenges containing benign mouth bacteria that can outcompete the harmful ones.

Personally, I used them for two months as directed, and saw no real difference.

Can't wait for a real product, I just hope it doesn't start off costing $200/month like some probiotics I've seen.

Curious: How would you observe a difference in two months? (HN being what it is, I'm half expecting you to tell me you were assaying your mouth bacteria with an electron microscope you made and some OpenCV hacked together on…)

Haha, no, no fancy electronics here. Just anecdotal observations.

I used mouthwash daily for a few years, established a baseline of how my mouth felt, and how my wife said it smelt. Used the tablet for 2 months, and felt no different, and she said I smelled no different.

It doesn't establish that Evora probiotics are useless, but I think it fairly establishes that they're not significantly better than just using mouthwash.

Wow, this is really interesting. Googling "C16G2" brought up some newer info. There's not much mainstream coverage, mostly just press releases and studies. But the company that's running with this is apparently called C3 Jian.

http://www.c3-jian.com/

They raised a $60M Series D in March of last year.

http://www.fiercebiotech.com/press-releases/c3-jian-closes-6...

They completed a Phase II clinical trial last Fall where they tested it as a mouthwash and a gel with three methods of application (tray, electric toothbrush, and manual toothbrush). Apparently gel in a tray won: 90% reduction in S. mutans population that lasted seven days after treatment ended.

http://globenewswire.com/news-release/2014/09/09/664615/1009...

C16G2 is the peptide that targets S. mutans. I suppose the idea is to develop more peptides targeting other species and give you a gel cocktail treatment (or maybe suppressing S. mutans is enough).

Being able to selectively kill exact species of bacteria ... that seems like a big deal.

There's a significant downside to this: in the long term, this leads to the evolution of super-resistant bacteria. I have little doubt this treatment will be effective in the short term but no idea what the rebound will look like.

Regarding resistance, they say:

"C16G2 works very rapidly in vitro with a unique membrane-active mechanism of action. This physical method of killing is not targeting a single gene product, and therefore single gene mutations are unlikely to confer resistance. Also, mechanism of action, route of administration and clearance of the drug are expected to limit drug exposure to the oral mucosa, so no impact on the development of resistance in other bacteria is expected, in contrast to concerns about overuse of traditional antibiotics. Despite believing resistance is not likely, we will carefully monitor resistance in clinical trials and in laboratory experiments."

http://www.c3-jian.com/technologies/frequently-asked-questio...

Thy made a genetically modified bacteria that doesn't produce lactic acid, and early trials seemed promising. But the FDA won't approve it. Also there are some other approaches to vaccinating against it.

Oral probiotics do exist. Look them up on Amazon. I tried taking them for 6 weeks but I really have no idea how to measure their effectiveness. I'd be curious if anyone has any insight on this.

uBiome (http://ubiome.com/) will sequence you microbiome for ~$100 - they support mouth, nose, gut & skin samples. If you're really interested, you could do one sample before, one after and get them both sequenced and compare the two.

I hope I live to see the day when the extent of oral hygiene maintenance and bad breath prevention is a toothpick and an occasional probiotic mouthwash or something.

What if you could do it now mostly with the right diet?

I would do it. As long as it didn't involve seafood. What are we talking, cheese and yogurt?

Short answer: Good quality sea salt and an alkaline diet.

I recently learned (via expensive vet visits) that some cats do need to have their teeth brushed daily, or else they risk decay and tooth loss. It's not just vet bs!

Does this same bacteria also cause strep throat? What about gum disease?

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